Occurrence of magnetic order on the basis of plutonium can be captured by LDA+U calculations.
Systematic investigation of diverse Pu compounds reveals that the 5f occupancy plays a key role.
If the 5f states are populated by more than approximately 5.3 electrons, the Pu magnetism vanishes.
For comparison with valence-band photoemission spectra, the Hubbard I method was used. It shows
consistently higher 5f5 final-state multiplet originating from the 5f6 admixture in the ground state
for those compounds which are nonmagnetic. The 5f occupancy can reach 5.6¿5.7 for Pu
monochalcogenides.